Hydro Flasks 21oz Standard Mouth Flex Cap is an essential hydration companion, featuring sleek stainless steel construction and a leakproof design. Thanks to TempShield double-wall vacuum insulation, it keeps drinks cold for 24 hours and hot for 12 hours, ensuring optimal temperatures on the go. BPA-free and dishwasher safe, it fits most cupholders, making it ideal for everyday use, whether at the gym or during outdoor adventures. Keep your drink refreshingly pure without flavour transfer.